Comprehensive damage index model for state assessment in structural health monitoring

Integrating two damage indexes for structural state assessment, the paper presents a comprehensive damage index model, accounting for both the maximum deformation and the cumulative damage. A typical reinforced concrete isolated bridge was analyzed under various earthquakes scaled to different peak ground acceleration levels, and then three other contradistinctive models were also calculated via the dynamic analysis. The result showed that the damage model which just accounts for the maximum deformation is logical under lower peak ground acceleration levels. However, the cumulative damage becomes distinct under higher peak ground acceleration levels. In addition, the effect of earthquake duration was also studied using the repeating EI Centro wave, which showed the same results.